Frequencies for first 10,000 rows of msa variable in namcs2013 dataset :

      Metropolitan Statistical Area |
       Status of physician location |      Freq.     Percent        Cum.
------------------------------------+-----------------------------------
MSA (Metropolitan Statistical Area) |      9,490       94.90       94.90
                            Non-MSA |        510        5.10      100.00
------------------------------------+-----------------------------------
                              Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017